Three days since it abruptly announced the cancellation of all summer sailings on the W.B. Yeats, Irish Ferries has moved or refunded 50pc of affected bookings, the company says.

5,746 bookings were thrown into disarray when the company announced further delays to the arrival of its €147 million W.B. Yeats ferry this Tuesday.

Around 19,000 customers were affected.

Of the affected bookings that have now been processed, 5.5pc have now been cancelled and refunded, while 92.7pc have been moved to alternate sailings, Irish Ferries says.

Less than 2pc of customers have opted for a land-bridge option, involving an extra car journey through the UK.

The W.B. Yeats was due to start sailing between Ireland and France in late July, but its delivery has been postponed until mid-September due to delays at Flensburger Schiffbau-Gesellschaft & Co. KG, the German shipbuilder.

Can anyone get through to #irishferries ? our sailings have been cancelled twice now and we can’t even get in touch to reschedule. Tried email, phone and now this.

Since Tuesday, affected customers have been scrambling to make alternative arrangements, with Irish Ferries drafting in extra customer service staff and extending the opening times of its phone lines to handle the crisis.

Many frustrated passengers have still taken to social media to complain about difficulties getting through to the helplines, however.

"Irish Ferries customer support team are still receiving a very high level of calls and messages and are working hard to get through them and will continue to do their best to deal with queries as soon as possible," it says.

Under EU regulations, passengers whose ferry sailings are cancelled or delayed have a right to a re-routing or a full reimbursement of the ticket price within seven days, as well as compensation in certain situations.

@Irish_Ferries do people have to contact you to reschedule, or are ye contacting all impacted customers? I got sorted through Twitter but my parents and my sister are also booked for the WB Yeats and have heard nothing yet.

Irish Ferries is offering alternative space on other ships, or a land-bridge option via the UK with the reimbursement of petrol/diesel expenses incurred.

It has also offered a €150 voucher as a goodwill gesture, but the voucher can only be claimed against holidays booked in 2019.

"Given the extraordinary circumstances causing these cancellations, which are outside of the company’s control, Irish Ferries is committed to assisting passengers in making alternative travel arrangements to France as best it can," the company says.

Competing ferry companies have been slow to post 'rescue'-style social media messages, though tour operator Topflight has offered a €200 discount on Italian holidays to "disappointed" passengers who show proof of their booking before June 30.

The W.B. Yeats is now likely to arrive in mid-September, when it will start sailing on the Dublin-Holyhead route, Irish Ferries says.